It’s estimated that our galaxy is littered with 100 million small black holes (several times the mass of our Sun) created from exploded stars. Like intense gravitational potholes in the fabric of space, virtually all black holes seem to come in two sizes: small and humongous. Koka Media, Universal Publishing Production Music France, and Universal Production MusicĪstronomers using NASA’s Hubble Space Telescope have come up with what they say is some of their best evidence yet for the presence of a rare class of “intermediate-sized” black hole that may be lurking in the heart of the closest globular star cluster to Earth, located 6,000 light-years away. Koka Media, Universal Publishing Production Music France, and Universal Production Music Koka Media, and Universal Production Music “Claraboo” by Denis Levaillant, Jean-Marc Foltz. Killer Tracks, Open Note, and Universal Production Music “Cascades” by Air Jared, Sebastian Barnaby Robertson. Over a decade ago, when she was new to the job, she had a special project related to the Hubble Space Telescope and its fifth and final servicing mission. Paula Cain is one of the talented thermal blanket technicians who uses her skillful hands to correctly cover all sorts of spacefaring instruments. "To do that, the next milestone is to measure the motion of the companion in its orbit.NASA’s Thermal Blanket Lab is a vital part of ensuring that the important equipment that we send into space remains protected from getting either too hot or too cold. "Our ultimate goal is to get an accurate mass for Polaris," Evans said. This in turn requires visual observation of their movements-something that was impossible with the Polaris binary system until now. ![]() But calculating the mass for each star in a binary setup requires knowledge of their complete orbits. Binary systems are important because their stars are among the few whose masses can be accurately determined. Knowing a Cepheid's mass is important to this understanding, but calculating the mass for most stars is difficult.Īlthough Polaris is a triple star system, it can be broken down into a binary system and a single star located farther away. Scientists use Cepheids to measure the distance to faraway galaxies and star clusters and to calculate the expansion rate of the universe. Polaris belongs to a special class of massive, pulsating stars known as Cepheids, which dim and brighten at regular intervals. It appears as a fixed point in the night sky around which all the other stars revolve, and sailors have long used it to orient themselves. It is situated almost directly above the celestial north pole, making it Earth's current northern polestar. ![]() Polaris is the brightest star in the constellation Ursa Minor and located about 431 light-years away. "With Hubble, we've pulled the North Star's companion out of the shadows and into the spotlight," said astronomer Howard Bond from the Space Telescope Science Institute, which operates Hubble for NASA and the European Space Agency. The research was presented here today in a press conference at the 207th meeting of the American Astronomical Society. "The companion is a little more massive than the Sun and a little brighter and a little hotter," Evans said.Įarly estimates suggest that Polaris is about four times more massive than the Sun, but the researchers hope to refine their estimate with observations about the companion star's orbit. The observations have helped researchers refine mass estimate for the main star and the newly photographed companion.
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